Method of making washable paper



' July 12, 1938. HT 2,123,399

METHOD OF MAKING WASHABLE PAPER Filed May 2, 1935 Patented July 12, 1938PATENT OFFICE- I 2,129,399 ME'rnop or name wnsnepnn. PAPER Charles G.Brlghia deceased, late of Appleton,

Wis., by Ruth E. Bright, Appleton, Wis., administratrix, assignor toPaper Patents Com-' sin pany, Neenah, Wis., a corporation or Wiscon-Application May 2, 1935, Serial No. 19,424 5 4 Claims.

Said invention relates to a waterproof paper and in its preferredembodiments contemplates .animproved paper which is especially suitablefor use as a decorative wall covering. Paper em- 5 bodying saidinvention, in addition to having high resistance to ordinary washingwith water and soap, is highly decorative andis preferably printed withone or more colors and embossed to' present a pleasing design to theeye.

In accordance with said invention, the process of manufacturing coatedand decorated paper of the type under consideration is considerablyshortened and simplified, resulting in substantial saving of time, spaceand equipment, and the cost is correspondingly reduced.

The base of said improved paper which has a water-resistant surface maybe printed upon with inks which are water-insoluble, i. e., in which thesolvent or liquid vehicle is other than water, e.'g., oil inks, so thatthe-finished surface is washable.

The ink, in the preferred method of practicing saidinvention, is printedat the bottom of depressions-ln' the embossing and it is thus possibleto wind up the printed and embossed paper without providing specialmeansfor drying the ink. The.

ink is permitted to dry in the roll and there is thus effected a greatsaving of equipment and space, such as are ordinarily used for dryingpaper of this type.

invention, a very thin, translucent coating may be applied, so thatcolored designs or decorative effects previously applied to the paperbase are not materially impaired or obscured. Also, such a coating tendsto softenthe design and, hence,

enhances the attractive appearance of the prod-,

uct.

According to another method, the coating may contain an opaque filler ofthe proper color. Various other features and advantages will becomeapparent as the description proceeds.

The accompanying drawing which forms part of this specificationillustrates diagrammatically one preferred-arrangement of apparatus forproducing paper in accordance with said invention.

The paper is made on a Fourdrinier machine.

It may be coated by the sieves-cloth method after partial drying orby'any other'suitable process or apparatus, for example, as shown inBright late cut 1,964,312, granted June 26, '1934. The paper may ,carrya *blend andcolor-drops, applied, for example, by the process andapparatus disclosed in United States Patent No, 1,595,207.

Where a thin and translucent coating is desired, as, for example, wherecolor-drops or blend In accordance with one mode of practicing said havebeen applied, the base coating material may be prepared as follows:

Two hundred poundsofcasein are soaked at F.- in 800 pounds of watercontaining 30 poundsof borax. The mixture is heated to F. and held atthis temperature for 20 to 25 min-' utes. One hundred sixty pounds ofmica are mixed with 600 pounds of water; and thecasein and micasolutions are mixed. Three pints of sulphonated pine oil and three pintsof pine oil 10 are added. to the above, which is then diluted with waterto 1,!!00 pounds. It will be understood, of course, that the formula maybe varied consider ably, and various other potentially water-insolublematerials may be used' in lieu of casein, such 15 as glue, vegetableprotein, etc. Also, other fillers than mica may be used, as would beapparent to one skilled lnthe art.

Where an opaque coating is desired, thebase coating material may contain'a' suitable per-.20 centage of opaque mineral, such asclay, or blancfixe. W

In 'the coating bath, whether translucent or opaque, one may include asetting agent for protein, such as formaldehyde, if desired. However, 25it is preferred to apply the setting agent, such as alum orformaldehyde,'on the paper machine or before the paper iswound up, forexample, at

the calender stacks, as will be described below.

Even though the fixing agent, in my'prefer'red 30 practice is applied asa separate operation, it may be, desirable to add a portion to thecoating mixture itself.

Referring now tothe drawing forming'part of this specification andillustrating diagrammat- 35 ically apparatus which may be used inpracticing said inventionz- Figure 1 is a diagrammatic'elevation, partlyin section, of paper-making apparatus which may be used in practicingsaid process; a

Figure 2 is an enlarged detail elevation showing a calender stack andmechanism associated therewith for applying a fixing solution to a paperweb as it passes through saidstack, and

Figure 3 is an enlarged detail elevation of'45- centration in water andapplied to paper for imparting a cloudy or other desired ornamentaleifect. The numeral indicates suction boxes.

From the paper machine thepaper web, indicated by the character W, isdrawn over drying cylinders, indicated generally-by the numeral Ii,whence it is conveyed to a coating device indicated at It. This-devicemay comprise a pan I'I containing a suitable coating material in fluiddrying of the ink may take place in the rolls. It will be apparent toone skilled in the art that 'there is thus effected a great saving inplant condition. Examples of suitable coating materials are givenabove.v After application of the coating i'rom the pan I! by the coatingrolls associated therewith, the web is subjected to a smoothinggoll '20associated with a trough 2| carrying a fluid similar to that carried bythe pan II. As explained in said Bright Patent No. 1,964,312, thesmoothing roll" preferably rotates in a direction opposite tothe web/W,the latter moving from left to right in Figure 1, and has associatedtherewith a doctor 22. It is believed I that the other elements of thecoating mechatheir. functions will be readily nism, such as the variousrolls in Figure 1 and apparent from the description shown in said BrightPatent 1,964,312.

The web W, after beingcoated, is conducted over-additional driers,indicated generally at 25, and thence passes tothe calender stackrepresented at 2'! and shown on an enlarged scale in Figure 2.Associated with the stack is a doctor 28 for applying to .the web asolution for fixing the potentially water-resistant binder which haspreviously been applied to-the web, e. g., formalin. Said solution maybe fed as bymeans of a con-- duit 29 from a receptacle 3!! and theexcess may bossing rolls beingfprovided. The roll be withdrawn. as bymeans of conduit 3|. The web may be conveyed from the stack, as at 32,to reels. There the fixing solution is permitted to react with thecoagulable material to render the coating water resistant.

Referring to Figure 3, the numeral 35 repre-' sents a reel of paperwhich has been coated and the coating insolubilized, as indicated above.The paper web P from said roll is conveyed over a pan 86 containingsteam for softening the sheet,

and it is then conveyed betweenprinting and em- 38 and 38', suitableguide rolls 38 38 may be considered a female roll, one of the rollssteel and bearing a suitable Ink and piga male roll and 3'' beingpreferably of ornamental design on its surface.

- ment are disposed in. a pan 40 from which it is picked up by means ofa roll II, which may be of copper. and thence conveyed by means ofleveling rollers 42 and II to the embossing roll ll.

After the web P 'has passed between the rolls I. and II where itis'simultaneously printed and em ossed, the web is drawn as'by the pullrollers 45 to a suitable reeling machine.

By means of the device shown in Figure 3 and more particularly the rolls'3. and 3|, ink is applied to the bottoms of the depressions formed bythe It is thus possible to reel the paper immediately after it isprinted and embossed, without any special device or space for drying.Since the. ink last the bottom of the depressions, the paper may ink iswet without any danger of smearing, and

space as well as in equipment, resulting in considerable economy.

The ink is preferably of an oil type, so that the sheet is completelywater-resistant and washare merely exemplary, but should be determinedfrom the appended claims, which are to be interpreted as broadly as thestate of the art will permit.

It is claimed:

1. A method for making washable wall paper,

comprising decorating a paper web while it is on the paper makingmachine, partially drying the-web, coating-said web with a compositionherein dis-' containing a potentiallywater-insoluble protein,

drying the coated web, fixing said coating by subjecting the same to afixing agent comprising one of the group consisting of alum andformaldehyde, softening the 'coated web and simultaneously embossingsaid web and printing on said web with a water-insoluble ink.

2. A method for making washable wall paper,

' comprising decorating a paper web while it is on the paper makingmachine, drying the web, coating said web with a composition containinga potentially water-insoluble protein, drying the coated web, fixingsaid coating by subjecting the same to a fixing agent comprising one ofthe group consisting of alum and/ formaldehyde, softening the coated webwith steam and simultaneously embossing said web and printing on saidweb with an oil ink.

3. A method of producing washable paper, comprising forming a paper webcarrying a potentially water-resistant protein coating in an aqueouscarrier, applying during the paper making operation a material whichwill chemically fix said coating, drying the web, then softening thedried coating and printing on said softened coating with awater-insoluble ink. r

4. A method of producing washable paper, comprising forming a paper webcarrying a potentially water-resistant protein coating in anaqueouscarrier, applying a material which will tion, drying the web,

be reeled while the.

Administratrix steaming the web to soften said coating, andsimultaneously embossing and printing said web at the bottom of thedepressions in the embossing with a water-insoluble ink.

RUTH E. BRIGHT,

of the Estate of Charles G. Bright, Deceased. I

